What is analgesic abuse nephropathy?
Prolonged use of analgesic mixtures containing phenacetin, paracetamol, aspirin, and/or NSAIDs may cause analgesic nephropathy.
The main site of kidney injury in analgesic nephropathy is the vascular endothelial cells in the kidney medulla, primarily because of low oxygen tension and toxin accumulation.
Occasionally, patients may present with flank pain or gross hematuria due to papillary necrosis. Papillary calcification and characteristic “bumpy” kidney contours may be seen on imaging. In some instances, the kidneys may appear bilaterally atrophic or asymmetric in size. Urinalysis may show sterile pyuria, microscopic or macroscopic hematuria, and mild proteinuria.
Patients with analgesic nephropathy are at increased risk for transitional cell carcinoma of the uroepithelium.
Management is primarily supportive and includes discontinuation of the culprit analgesic agent. Close monitoring, especially for development of new symptoms, such as gross hematuria, is recommended because of the increased risk of uroepithelial tumors.
